LT1 Runs Finally - No more DTC 46

[Joe Gervais]

Thanks to the help on these two lists, I got the 93 LT1 motor in my 61 Vette
running today. The prom images with no vats apparently didn't have VATS
disabled properly, because the injectors didn't stay running.

Knowing that the Fbody has an easily defeatable VATS, I got the proper input
for the ECM from Scot on the DIY_EFI list, and built a $5 timer circuit using a
555 IC to bypass the thing. I should have done this a couple of months ago, but
oh well.

Now the race is on. There's the GG Summer Get Together in 4 weeks. I may need a
body dropapaloosa at my house in a couple of weeks to make the show. The car
will certainly be on the road by July.

I taped the motor, so I'll have an audio file up on reality in a day or two.
 I'll have to see how it is with tailpipes, but right now, the bare chassis
with the straight 2.5" exhaust and 3 chamber Flowmasters is bordering on too
loud, although it is a good tone. Given I didn't roll the chassis into the
driveway, and had the sound bouncing off the back wall of the garage didn't
help. My kids came running from the park a good 1/8 mile away, so it's got
audible punch.

VATS bypass details

For 93 FBody, ECM 16159278, terminal A19 on the ECM needs a 30 Hz signal, 50%
duty cycle.

For 94 and possibly 95 with PCM 16188051 terminal A25 on the PCM needs a 50 Hz
signal.

Alan wrote "In my 94 Helms, it sez terminal A25 on PCM. The name of the wire
going to this terminal is 229 DK BLU - it may be on your harness. If 40-60Hz is
not present on this terminal, engine will stall after 1.7 seconds.", which is
exactly what was happening on my motor.

-- 
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Joe Gervais                   gervais at sgi.com
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